The jet diffuser ejector disclosed in U.S. Pat. No. 4,332,529 is disclosed in the form of a rectangular configuration having a relatively short length in the direction of the thrust axis of the ejector for maximizing thrust augmentation with minimal volumetric requirements. The principal characteristic of the jet diffuser ejector disclosed in said U.S. Pat. No. 4,332,529 is that relative to conventional ejectors, it has a relatively short length in the thrust direction of the ejector with a diffusing section having relatively large angles of divergence greater than 7.degree. to 8.degree. so as to cause the core fluids to diffuse beyond the discharge end of the solid surface of the ejector without separation. This can cause divergence of the discharge fluids to one-half angles as large as 60.degree. without adverse effects on performance. The wide angle, high performance and relative short length achieved by this type of ejector is primarily due to the diffusing section of the patented ejecting structure which comprises upstream and downstream solid sections and a diffuser jet. The downstream solid diffusing section has a large area ratio and terminates in a divergence angle as large as can possibly be utilized in a particular application. The diffuser jet comprises a nozzle completely surrounding the periphery and incorporated between the downstream and upstream solid diffuser surfaces to introduce a fluid jet to prevent separation of the conveyed fluids from the solid wall downstream of the jet. The diffuser jet fluid forms a jet sheet, increasing the effective diffuser area ratio and causing all the mixed fluids to diffuse beyond the solid diffuser surface.
The method and apparatus for spraying disclosed in copending patent application Ser. No. 367,432 utilizes the basic jet diffuser ejector of the type disclosed in said U.S. Pat. No. 4,332,529, as the preferred embodiment. The ejector, however, has been modified for conveying a spray substance through the ejecting structure in combination with the usual mixed core fluids. For this purpose, the disclosed ejector has a circular cross-sectional configuration, and is provided with a plurality of means for introducing a spray substance into the ejector.
The problems associated with the achievement of smooth, unseparated flow in the corners and along the lateral sides of the rectangular ejector as originally developed and disclosed in U.S. Pat. No. 4,332,529 is resolved by utilizing flat nondiverging solid diffuser ends. Later designs were developed for use in aiding and avoiding the end problems and permitting the use of diverging ends. These prior art techniques have been published in the Journal of Aircraft in an article entitled "Recent Developments of a Jet-Diffuser Ejector", by Morton Alperin and Jiunn-Jenq Wu, in December, 1981, pages 1011 through 1018. As noted in said Journal of Aircraft publication, the developments were disclosed at a technical meeting of the American Institute of Aeronautics and Astronautics in January 1980, in Pasadena, Calif. To adapt the jet diffuser ejector of the type disclosed in U.S. Pat. No. 4,332,529 to the vertical takeoff of high-speed aircraft it required that the primary nozzles for the ejector be stowed during the high-speed portion of flight to avoid excessive drag. A rectangular jet diffuser ejector having the attached nozzle design was also disclosed in the publication of Alperin and Wu entitled "Jet Diffuser Ejector-Attached Nozzle Design", NASA CR152361, May 1980.